TOKYO (AP) — An international donor meeting for Afghanistan that is expected to bring pledges of $16 billion in aid over the next four years has begun in Tokyo.

The meeting, attended by about 70 countries and organizations, will set aid levels in a crucial period for Afghanistan as most foreign combat troops leave the war-torn country.

U.S. officials traveling with Secretary of State Hillary Rodham Clinton said they expected the donors to pledge $16 billion, which would be in line with the nearly $4 billion per year the Japanese co-hosts had said they were hoping to achieve during the Sunday conference.

The donors are also expected to set up review and monitoring measures to assure the aid is used for development and not wasted by corruption or mismanagement.

The U.S. portion is expected to be in the decade-long annual range of $1 billion to this year’s $2.3 billion. Officials declined to outline the future annual U.S. allotments going forward, but the Obama administration has requested a similarly high figure for next year as it draws down American troops and hands over greater authority to Afghan forces.

The total amount of international civilian support represents a slight trailing off from the current annual level of around $5 billion, a number somewhat inflated by U.S. efforts to effect a “civilian surge” for Afghan reconstruction, mirroring President Barack Obama’s decision in 2009 to ramp up military manpower in the hopes of routing the Taliban insurgency.

Still, it is a large sum of cash designed to allay fears that Afghanistan will be abandoned when NATO and other international soldiers leave the country.

It will come with conditions, as well, with the donors’ meeting in Japan expected to establish a road map of accountability to ensure that Afghanistan does more to improve governance and finance management, and to safeguard the democratic process, rule of law and human rights — especially those of women.

Foreign aid in the decade since the U.S. invasion in 2001 has led to better education and health care, with nearly 8 million children, including 3 million girls, enrolled in schools. That compares with 1 million children more than a decade ago, when girls were banned from school under the Taliban.

Improved health facilities have halved child mortality and expanded basic health services to nearly 60 percent of Afghanistan population of more than 25 million, compared with less than 10 percent in 2001.

But donors have become wary of corruption-busting pledges that have not always been delivered. Some highly placed Afghan officials have been investigated for corruption but seldom prosecuted, and some of the graft investigations have come close to the president himself.

The stakes for Afghan President Hamid Karzai are high as he faces international weariness with the war and frustration over his failure to crack down on corruption more than a decade after the U.S. invasion that ousted the Taliban.

Afghanistan has received nearly $60 billion in such aid since 2002. The World Bank says foreign aid makes up nearly the equivalent of the country’s gross domestic product.

Those funds, which are needed for basic services such as health care, education and infrastructure, are expected to sharply diminish after international troops withdraw even as the country faces continued threats from the Taliban and other Islamic militants.

The $4 billion in annual civilian aid for comes on top of $4.1 billion in yearly assistance pledged last May at a NATO conference in Chicago to fund the Afghan National Security Forces from 2015 to 2017.

Clinton, who briefly visited the Afghan capital on Saturday before heading to Tokyo, had breakfast with Karzai and acknowledged that corruption was a “major problem.”

“We’re working hard with our Afghan partners to address this problem here in Afghanistan, knowing that it’s much broader than Afghanistan by promoting greater transparency, the rule of law, good governance, working hard to prevent fraud, waste and abuse,” she told reporters.

“We’re working with the Afghanistan ministries, governors, local leaders who are committed to delivering services to their people, improving their lives,” Clinton added. “We take seriously any allegations of corruption that involve U.S. funds.”

Clinton also declared Afghanistan as the newest “major non-NATO ally” of the United States, a gesture of political support for the country’s long-term stability and aimed at solidifying close defense cooperation after American combat troops withdraw in 2014.

“We see this as a powerful commitment to Afghanistan’s future,” Clinton said. “We are not even imagining abandoning Afghanistan.”